1 files changed, 388 insertions, 0 deletions

diff --git a/drivers/net/ethernet/aquantia/atlantic/aq_ring.c b/drivers/net/ethernet/aquantia/atlantic/aq_ring.c
new file mode 100644
index 000000000..b03e5fd43
--- /dev/null
+++ b/drivers/net/ethernet/aquantia/atlantic/aq_ring.c
@@ -0,0 +1,388 @@
+/*
+ * aQuantia Corporation Network Driver
+ * Copyright (C) 2014-2017 aQuantia Corporation. All rights reserved
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ */
+
+/* File aq_ring.c: Definition of functions for Rx/Tx rings. */
+
+#include "aq_ring.h"
+#include "aq_nic.h"
+#include "aq_hw.h"
+
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+
+static struct aq_ring_s *aq_ring_alloc(struct aq_ring_s *self,
+				       struct aq_nic_s *aq_nic)
+{
+	int err = 0;
+
+	self->buff_ring =
+		kcalloc(self->size, sizeof(struct aq_ring_buff_s), GFP_KERNEL);
+
+	if (!self->buff_ring) {
+		err = -ENOMEM;
+		goto err_exit;
+	}
+	self->dx_ring = dma_alloc_coherent(aq_nic_get_dev(aq_nic),
+						self->size * self->dx_size,
+						&self->dx_ring_pa, GFP_KERNEL);
+	if (!self->dx_ring) {
+		err = -ENOMEM;
+		goto err_exit;
+	}
+
+err_exit:
+	if (err < 0) {
+		aq_ring_free(self);
+		self = NULL;
+	}
+	return self;
+}
+
+struct aq_ring_s *aq_ring_tx_alloc(struct aq_ring_s *self,
+				   struct aq_nic_s *aq_nic,
+				   unsigned int idx,
+				   struct aq_nic_cfg_s *aq_nic_cfg)
+{
+	int err = 0;
+
+	self->aq_nic = aq_nic;
+	self->idx = idx;
+	self->size = aq_nic_cfg->txds;
+	self->dx_size = aq_nic_cfg->aq_hw_caps->txd_size;
+
+	self = aq_ring_alloc(self, aq_nic);
+	if (!self) {
+		err = -ENOMEM;
+		goto err_exit;
+	}
+
+err_exit:
+	if (err < 0) {
+		aq_ring_free(self);
+		self = NULL;
+	}
+	return self;
+}
+
+struct aq_ring_s *aq_ring_rx_alloc(struct aq_ring_s *self,
+				   struct aq_nic_s *aq_nic,
+				   unsigned int idx,
+				   struct aq_nic_cfg_s *aq_nic_cfg)
+{
+	int err = 0;
+
+	self->aq_nic = aq_nic;
+	self->idx = idx;
+	self->size = aq_nic_cfg->rxds;
+	self->dx_size = aq_nic_cfg->aq_hw_caps->rxd_size;
+
+	self = aq_ring_alloc(self, aq_nic);
+	if (!self) {
+		err = -ENOMEM;
+		goto err_exit;
+	}
+
+err_exit:
+	if (err < 0) {
+		aq_ring_free(self);
+		self = NULL;
+	}
+	return self;
+}
+
+int aq_ring_init(struct aq_ring_s *self)
+{
+	self->hw_head = 0;
+	self->sw_head = 0;
+	self->sw_tail = 0;
+	return 0;
+}
+
+static inline bool aq_ring_dx_in_range(unsigned int h, unsigned int i,
+				       unsigned int t)
+{
+	return (h < t) ? ((h < i) && (i < t)) : ((h < i) || (i < t));
+}
+
+void aq_ring_update_queue_state(struct aq_ring_s *ring)
+{
+	if (aq_ring_avail_dx(ring) <= AQ_CFG_SKB_FRAGS_MAX)
+		aq_ring_queue_stop(ring);
+	else if (aq_ring_avail_dx(ring) > AQ_CFG_RESTART_DESC_THRES)
+		aq_ring_queue_wake(ring);
+}
+
+void aq_ring_queue_wake(struct aq_ring_s *ring)
+{
+	struct net_device *ndev = aq_nic_get_ndev(ring->aq_nic);
+
+	if (__netif_subqueue_stopped(ndev, ring->idx)) {
+		netif_wake_subqueue(ndev, ring->idx);
+		ring->stats.tx.queue_restarts++;
+	}
+}
+
+void aq_ring_queue_stop(struct aq_ring_s *ring)
+{
+	struct net_device *ndev = aq_nic_get_ndev(ring->aq_nic);
+
+	if (!__netif_subqueue_stopped(ndev, ring->idx))
+		netif_stop_subqueue(ndev, ring->idx);
+}
+
+bool aq_ring_tx_clean(struct aq_ring_s *self)
+{
+	struct device *dev = aq_nic_get_dev(self->aq_nic);
+	unsigned int budget;
+
+	for (budget = AQ_CFG_TX_CLEAN_BUDGET;
+	     budget && self->sw_head != self->hw_head; budget--) {
+		struct aq_ring_buff_s *buff = &self->buff_ring[self->sw_head];
+
+		if (likely(buff->is_mapped)) {
+			if (unlikely(buff->is_sop)) {
+				if (!buff->is_eop &&
+				    buff->eop_index != 0xffffU &&
+				    (!aq_ring_dx_in_range(self->sw_head,
+						buff->eop_index,
+						self->hw_head)))
+					break;
+
+				dma_unmap_single(dev, buff->pa, buff->len,
+						 DMA_TO_DEVICE);
+			} else {
+				dma_unmap_page(dev, buff->pa, buff->len,
+					       DMA_TO_DEVICE);
+			}
+		}
+
+		if (unlikely(buff->is_eop)) {
+			++self->stats.rx.packets;
+			self->stats.tx.bytes += buff->skb->len;
+
+			dev_kfree_skb_any(buff->skb);
+		}
+		buff->pa = 0U;
+		buff->eop_index = 0xffffU;
+		self->sw_head = aq_ring_next_dx(self, self->sw_head);
+	}
+
+	return !!budget;
+}
+
+static void aq_rx_checksum(struct aq_ring_s *self,
+			   struct aq_ring_buff_s *buff,
+			   struct sk_buff *skb)
+{
+	if (!(self->aq_nic->ndev->features & NETIF_F_RXCSUM))
+		return;
+
+	if (unlikely(buff->is_cso_err)) {
+		++self->stats.rx.errors;
+		skb->ip_summed = CHECKSUM_NONE;
+		return;
+	}
+	if (buff->is_ip_cso) {
+		__skb_incr_checksum_unnecessary(skb);
+	} else {
+		skb->ip_summed = CHECKSUM_NONE;
+	}
+
+	if (buff->is_udp_cso || buff->is_tcp_cso)
+		__skb_incr_checksum_unnecessary(skb);
+}
+
+#define AQ_SKB_ALIGN SKB_DATA_ALIGN(sizeof(struct skb_shared_info))
+int aq_ring_rx_clean(struct aq_ring_s *self,
+		     struct napi_struct *napi,
+		     int *work_done,
+		     int budget)
+{
+	struct net_device *ndev = aq_nic_get_ndev(self->aq_nic);
+	int err = 0;
+	bool is_rsc_completed = true;
+
+	for (; (self->sw_head != self->hw_head) && budget;
+		self->sw_head = aq_ring_next_dx(self, self->sw_head),
+		--budget, ++(*work_done)) {
+		struct aq_ring_buff_s *buff = &self->buff_ring[self->sw_head];
+		struct sk_buff *skb = NULL;
+		unsigned int next_ = 0U;
+		unsigned int i = 0U;
+		struct aq_ring_buff_s *buff_ = NULL;
+
+		if (buff->is_error) {
+			__free_pages(buff->page, 0);
+			continue;
+		}
+
+		if (buff->is_cleaned)
+			continue;
+
+		if (!buff->is_eop) {
+			for (next_ = buff->next,
+			     buff_ = &self->buff_ring[next_]; true;
+			     next_ = buff_->next,
+			     buff_ = &self->buff_ring[next_]) {
+				is_rsc_completed =
+					aq_ring_dx_in_range(self->sw_head,
+							    next_,
+							    self->hw_head);
+
+				if (unlikely(!is_rsc_completed)) {
+					is_rsc_completed = false;
+					break;
+				}
+
+				if (buff_->is_eop)
+					break;
+			}
+
+			if (!is_rsc_completed) {
+				err = 0;
+				goto err_exit;
+			}
+		}
+
+		/* for single fragment packets use build_skb() */
+		if (buff->is_eop &&
+		    buff->len <= AQ_CFG_RX_FRAME_MAX - AQ_SKB_ALIGN) {
+			skb = build_skb(page_address(buff->page),
+					AQ_CFG_RX_FRAME_MAX);
+			if (unlikely(!skb)) {
+				err = -ENOMEM;
+				goto err_exit;
+			}
+
+			skb_put(skb, buff->len);
+		} else {
+			skb = netdev_alloc_skb(ndev, ETH_HLEN);
+			if (unlikely(!skb)) {
+				err = -ENOMEM;
+				goto err_exit;
+			}
+			skb_put(skb, ETH_HLEN);
+			memcpy(skb->data, page_address(buff->page), ETH_HLEN);
+
+			skb_add_rx_frag(skb, 0, buff->page, ETH_HLEN,
+					buff->len - ETH_HLEN,
+					SKB_TRUESIZE(buff->len - ETH_HLEN));
+
+			if (!buff->is_eop) {
+				for (i = 1U, next_ = buff->next,
+				     buff_ = &self->buff_ring[next_];
+				     true; next_ = buff_->next,
+				     buff_ = &self->buff_ring[next_], ++i) {
+					skb_add_rx_frag(skb, i,
+							buff_->page, 0,
+							buff_->len,
+							SKB_TRUESIZE(buff->len -
+							ETH_HLEN));
+					buff_->is_cleaned = 1;
+
+					if (buff_->is_eop)
+						break;
+				}
+			}
+		}
+
+		skb->protocol = eth_type_trans(skb, ndev);
+
+		aq_rx_checksum(self, buff, skb);
+
+		skb_set_hash(skb, buff->rss_hash,
+			     buff->is_hash_l4 ? PKT_HASH_TYPE_L4 :
+			     PKT_HASH_TYPE_NONE);
+
+		skb_record_rx_queue(skb, self->idx);
+
+		++self->stats.rx.packets;
+		self->stats.rx.bytes += skb->len;
+
+		napi_gro_receive(napi, skb);
+	}
+
+err_exit:
+	return err;
+}
+
+int aq_ring_rx_fill(struct aq_ring_s *self)
+{
+	unsigned int pages_order = fls(AQ_CFG_RX_FRAME_MAX / PAGE_SIZE +
+		(AQ_CFG_RX_FRAME_MAX % PAGE_SIZE ? 1 : 0)) - 1;
+	struct aq_ring_buff_s *buff = NULL;
+	int err = 0;
+	int i = 0;
+
+	for (i = aq_ring_avail_dx(self); i--;
+		self->sw_tail = aq_ring_next_dx(self, self->sw_tail)) {
+		buff = &self->buff_ring[self->sw_tail];
+
+		buff->flags = 0U;
+		buff->len = AQ_CFG_RX_FRAME_MAX;
+
+		buff->page = alloc_pages(GFP_ATOMIC | __GFP_COMP, pages_order);
+		if (!buff->page) {
+			err = -ENOMEM;
+			goto err_exit;
+		}
+
+		buff->pa = dma_map_page(aq_nic_get_dev(self->aq_nic),
+					buff->page, 0,
+					AQ_CFG_RX_FRAME_MAX, DMA_FROM_DEVICE);
+
+		if (dma_mapping_error(aq_nic_get_dev(self->aq_nic), buff->pa)) {
+			err = -ENOMEM;
+			goto err_exit;
+		}
+
+		buff = NULL;
+	}
+
+err_exit:
+	if (err < 0) {
+		if (buff && buff->page)
+			__free_pages(buff->page, 0);
+	}
+
+	return err;
+}
+
+void aq_ring_rx_deinit(struct aq_ring_s *self)
+{
+	if (!self)
+		goto err_exit;
+
+	for (; self->sw_head != self->sw_tail;
+		self->sw_head = aq_ring_next_dx(self, self->sw_head)) {
+		struct aq_ring_buff_s *buff = &self->buff_ring[self->sw_head];
+
+		dma_unmap_page(aq_nic_get_dev(self->aq_nic), buff->pa,
+			       AQ_CFG_RX_FRAME_MAX, DMA_FROM_DEVICE);
+
+		__free_pages(buff->page, 0);
+	}
+
+err_exit:;
+}
+
+void aq_ring_free(struct aq_ring_s *self)
+{
+	if (!self)
+		goto err_exit;
+
+	kfree(self->buff_ring);
+
+	if (self->dx_ring)
+		dma_free_coherent(aq_nic_get_dev(self->aq_nic),
+				  self->size * self->dx_size, self->dx_ring,
+				  self->dx_ring_pa);
+
+err_exit:;
+}